Spectral imaging, including hyperspectral imaging, can provide spectral information from one or more points of an object. Hyperspectral imaging can combine spatial imaging and spectroscopy. For each coordinate position of an object, a hyperspectral imager obtains the light intensity for a large number, e.g., more than 10, or more than 100 spectral bands. Every position in the hyperspectral image thus contains the spectrum of the light at its corresponding object position. The hyperspectral image data can be used to characterize features of the object with precision and detail. Spectral imaging has applications in many fields including agriculture, astronomy, and biomedical imaging.